KUMAR, Y.; PILLAI, N.; SHARMA, R. On the Number of Integer Recurrence Relations. Defence Science Journal, [S. l.], v. 66, n. 6, p. 605–611, 2016. DOI: 10.14429/dsj.66.10801. Disponível em: https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/10801. Acesso em: 15 jun. 2025.